1. Field of the Disclosure
The present disclosure relates to an oscillating nozzle sprinkler in which match precipitation adjustment is provided. More specifically, the present application relates to an oscillating nozzle sprinkler with adjustable arc of coverage setting including integrated automatic flow rate adjustment such that the flow rate changes with the arc of coverage to automatically provide a matched precipitation rate without the need to change nozzles.
2. Related Art
U.S. Pat. Nos. 4,867,378 and 4,901,924 disclose oscillating sprinklers with adjustable arcs of coverage and an indicator on the top of the nozzle that displays the selected arc angle. U.S. Pat. No. 5,417,370 discloses a reversing gear drive with a settable arc of oscillation. These references illustrate several drive mechanisms for oscillating sprinklers in which the arc of coverage is easily adjustable, and which provide an indication of the selected arc angle on the top of the nozzle housing. Other types of drive mechanisms such as ball drives and reversing turbine gear drives can also be used in such sprinklers.
U.S. Pat. No. 5,098,021 relates to an oscillating nozzle sprinkler with integrated adjustability of both arc of coverage and flow. In this patent, the selected flow rate (or the corresponding precipitation rate) is displayed on the top of the nozzle separately from the selected arc setting. This patent also discloses a nozzle configuration with an adjustable throat plug for changing the flow rate through the nozzle and various configurations for providing different water distribution patterns
U.S. Pat. No. 5,086,977 relates to an oscillating water driven sprinkler having a nozzle in which the stream elevation angle or spray range is adjustable from the top surface of the nozzle using a screw mechanism.
U.S. Pat. No. 6,237,862 relates to a nozzle configuration in which the nozzle tube is surrounded by and attached to a flexible thin diaphragm. The shape of the diaphragm allows the nozzle tube to be effectively hinged so that deflecting the nozzle tube establishes a desired sprinkler stream exit angle.
The above-mentioned U.S. Pat. Nos. 4,867,378, 4,901,924, 5,417,370, 5,098,021, and 6,237,862 provide general, technical background, and further physical and mechanical background for the features and improvements of the present application and are hereby incorporated by reference herein as if fully disclosed.
None of these patents, however, nor any other sprinklers known to applicant, provide the capability for automatic adjustment of the flow to maintain a preset precipitation rate as the spray range and/or arc of coverage is adjusted. None of these references disclose maintaining a constant precipitation rate if a pre-selected spray range, or arc of coverage is changed in the field, or even recognize how the precipitation rate is affected by such changes without performing a laborious calculation, which is rarely, if ever, done in practice
This can be a significant inconvenience in some instances. For example, in arranging uniform coverage of the area under irrigation, sprinklers are often arranged in a triangular pattern, and adjusted for maximum range. Sometimes, however, best coverage can be obtained with a square, or in-line pattern, or with combinations of sprinklers grouped in different patterns. In addition, the installer may need to adjust the ranges and arc angles of some or all of the sprinklers at the time of installation. Since it is important that the precipitation rates of individual sprinklers or groups of sprinklers be matched for uniform precipitation and the flow for a given precipitation rate varies with the spray range and arc angle, it has been practically impossible to preset the flow for a desired precipitation rate. It has thus been customary to install different nozzles at different locations in complex layouts in order to achieve reasonably uniform precipitation.
A need clearly exists for a sprinkler in which the arc angle, spray range, and precipitation rate are adjustable, and in which a desired precipitation rate can be set and maintained by automatic changes in the flow rate as adjustments of the arc angle and spray range are made by the user.
U.S. Pat. No. 6,732,952 discloses an oscillating nozzle sprinkler with integrated adjustable arc, precipitation rate, flow rate and range of coverage adjustment. However, this reference also fails to disclose a sprinkler assembly in which flow control is provided automatically as a function of arc of coverage adjustment to provide a constant precipitation rate
Accordingly, it would be desirable to provide an oscillating nozzle assembly that provides for an adjustable arc of coverage and avoids the problems discussed above.